Notably, Skype 2.0 for Windows includes video. The company is offering free one-to-one audio-video calls. The update also promises better voice quality. Currently, 2.0 is available only for Windows 2000 or XP.

Skype 1.4 for Mac OSX, however, has some significant upgrades, including the addition of call forwarding and call auto-answer. Users also can set up calls quicker and receive notification of new messages.

Version 1.4 can automatically pause iTunes when a call is answered.

And, for the first time, the Mac version is available in Japanese, said Skype, which is owned by eBay Inc.

Version 1.4 works with Mac OSX v10.3 or newer.